Identifying the source of unexpected lighting differences
Many of the objects have custom split normals data that need to be removed. This is fairly common with objects imported from other software, and is good to check when running into any shading issues with imported objects that aren't simply resolved.
To fix, simply go to Object Data&gt;Geometry Data&gt;Clear Custom Split Normals for each problem object. To speed up the process, you could use ⇧ Shift + R after selecting the next tooth to repeat the last operator. See the gif below for an example: